The invention relates to a turbine ring assembly comprising a plurality of ring sectors made of ceramic matrix composite material, together with a ring support structure.
With turbine ring assemblies made entirely out of metal, it is necessary to cool all of the elements of the assembly and in particular the turbine ring that is subjected to the hottest streams. Such cooling has a significant impact on the performance of the engine since the cooling stream that is used is taken from the main stream of the engine. In addition, the use of metal for the turbine ring limits potential for increasing the temperature in the turbine, even though that would make it possible to improve the performance of aeroengines.
In an attempt to solve those problems, proposals have been made for turbine ring sectors to be made out of ceramic matrix composite (CMC) material in order to avoid using a metal material.
CMC materials present good mechanical properties making them suitable for constituting structural elements, and advantageously they conserve these properties at high temperatures. The use of CMC materials has advantageously made it possible to reduce the cooling stream that needs to be used in operation, and thus to increase the performance of turbine engines. In addition, using CMC materials serves advantageously to reduce the weight of turbine engines and to reduce the effect of expansion while hot that is encountered with metal parts.
Nevertheless, existing solutions that have been proposed can involve assembling a CMC ring sector with metal attachment portions of a ring support structure, which attachment portions are subjected to the hot stream. Consequently, those assembly solutions can still require a cooling stream to be used, at least for cooling said metal attachment portions. In addition, the metal attachment portions expand when hot, which can lead to putting stress on CMC ring sectors and to weakening them.
There therefore exists a need to improve existing turbine ring assemblies that use a CMC material in order to further reduce the quantity of cooling gas that is needed.
There also exists a need to improve existing turbine ring assemblies using CMC material in order to reduce the magnitude of the mechanical stresses to which the CMC ring sectors are subjected in operation.